1. Field of the Invention
The present invention relates to a plasma display panel and a method of manufacturing the same. In particular, the present invention relates to a plasma display panel having a modified structure of barrier ribs for applying a phosphor layer effectively, and a method of manufacturing the same.
2. Description of the Related Art
A plasma display panel (PDP) is typically a display device in which vacuum ultraviolet light from plasma generated by gas discharge excites phosphors to emit visible light for producing an image. The PDP has received much attention as a next generation thin display device due to various advantageous features, such as its suitability for large screen sizes and its high resolution. PDPs may be classified into direct current (DC), alternating current (AC) and hybrid types. Recently, a three-electrode type surface discharge AC PDP has been of particular interest.
On a rear substrate of the three-electrode type surface discharge AC PDP, address electrodes, barrier ribs and a phosphor layer are formed at positions corresponding to each discharge cell. Display electrodes consisting of scan electrodes and sustain electrodes are formed on a front substrate. The discharge cells are defined and divided by the barrier ribs and filled with a discharge gas.
A discharge cell for light emission is selected by a signal voltage applied between the address electrode and the scan electrode. A plasma discharge then takes place inside the selected discharge cell, induced by a voltage of about 150 to 200 V applied between the sustain electrode and the scan electrode. Vacuum ultraviolet light is emitted from exited Xe atoms in the selected discharge cell during the plasma discharge. The vacuum ultraviolet light excites the phosphor layer in the discharge cell to emit visible light for an image.
The PDP may include non-discharge areas formed among the discharge cells for improving luminous efficiency and bright room contrast of the PDP. Where the non-discharge area is fully opened in one direction, i.e., has a channel-like structure, discharge cell shrink may cause the barrier ribs to become distorted. In order to reduce the chances of distortion, bridge-type barrier rib members may be formed at intervals along the non-discharge area to support and reinforce the barrier ribs. These bridge-type barrier rib members may intersect the non-discharge areas so as to break up the channel-like structure of the non-discharge area into non-discharge cells.
In the manufacture of PDPs having the above-described structures, the phosphor layer has typically been formed by printing or coating the phosphor onto the substrate having the barrier ribs. However, printing the phosphor has generally resulted in higher cost due to the necessity of providing a screen mask for individual phosphor colors. The high cost of printing, combined with the lower throughput of the printing process, has made coating processes more attractive for high-volume mass production of PDPs.
In the coating process, each of the R (red), G (green), B (blue) phosphors may be separately applied, and may be applied continuously from a dispenser while passing the dispenser over the appropriate discharge cells. However, due to the continuous nature of the application, phosphor is also delivered to non-discharge areas that lie in the path of application. That is, the dispenser may not interrupt its delivery of the phosphor when it passes over a non-discharge area. Furthermore, the coating process may also dispense the phosphors on the bridge-type barrier rib members defining the non-discharge cells, which may then cause the phosphors to overflow into neighboring discharge cells. The overflow of phosphors results in the mixing of phosphor colors in the discharge cells, degrading the display quality of the PDP.